Odyssey's Gamma Ray Spectrometer Instrument Deployed

Flight controllers for NASA's Mars Odyssey spacecraft completed the last major technical milestone today in support of the science mission by unfurling the boom that holds the gamma ray spectrometer sensor head instrument.

Engineers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., received confirmation from the spacecraft that the 6.2-meter (20-foot) boom was successfully deployed at noon Pacific time.

The gamma sensor head is part of the gamma ray spectrometer suite. It sits at the end of the boom to minimize interference from any gamma rays coming from the spacecraft itself. The two other gamma ray spectrometer instruments, the neutron spectrometer and the high-energy neutron detector, are mounted on the main spacecraft structure.

During the past few months, while the boom was in the stowed position, the instrument suite has provided significant information about the hydrogen abundance on Mars. This allowed scientists to conclude there are large quantities of water ice just below the surface.

"Deploying the boom enhances the sensitivity and accuracy of the gamma ray spectrometer instrument and will improve the accuracy of the hydrogen measurements," said Dr. William Boynton, principal investigator for Odyssey's gamma ray spectrometer suite at the University of Arizona, Tucson. Now the instrument will begin measuring many other important elements such as iron, aluminum, potassium, chlorine, thorium, uranium and others.

"Today's deployment is a continuation of the excellent performance of this flight team. They have done an outstanding job," said Roger Gibbs, Odyssey's project manager at JPL. "I look forward to many exciting discoveries to come as we continue our mission."

JPL manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. Principal investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, operate the science instruments. Additional science investigators are located at the Russian Space Research Institute and Los Alamos National Laboratories, New Mexico. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.